-38.19% is the change from 830 to 513
Calculation steps:
[( 513 - 830 ) ÷ 830] x 100 = -38.19%
Formula
Percentage change = [(513 - 830) / 830] x 100
Subtract the new number by the original number
513 - 830 = -317
-317 ÷ 830 = -0.3819277108433735
-0.3819277108433735 x 100 = -38.19%